Lady Rain has great advice there. i would like to add, well after u unplug the system of course & that u are free of static electricity, to unplug the RAM, and/or graphic card then plug 'em back in again. as what the lady said, it might be loose connection. u can also try cleaning the electrical connection (those rows of golden teeth, to borrow Lady Rain's expression) by using a soft pencil eraser.

let's hope it's not the motherboard. & i also hope it's not the power supply unit too.

sorry can't help u more there, Cleg.

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